With Touré, a hugely influential player at City, tied to a long contract, it seems unlikely the club would consider allowing him to go.

Seluk said in his latest complaint, via the Sun: "Yaya is so upset he's thinking of leaving City. There are a number of things that have happened that have left Yaya feeling bitterly upset. He must concentrate on the World Cup now. But City have treated him with disrespect and have really hurt him."

Seluk added: "They don't know that money can't buy relationships – no Sheikh can buy a relationship. This isn't about money or a new contract – it's about human relationships and City have shown they don't respect him. I repeat, this is not about money. In fact, he would take less to return to Barcelona."

In reference to the birthday snub, Seluk said: "What happened at his birthday meant the club don't care about him. It was proof. They can say whatever they want, 'Oh we like him but we forgot'.

"Forgot? About Yaya? The player who helped you to be two-times Premier League champions? The guy who helped you win the FA Cup and the League Cup? His birthday can be on a normal day and, in a normal team, his team-mates and club would at least give him good wishes. But when you win the title on May 11, a day later you go to Abu Dhabi and on May 13 you have a big party to celebrate the title and nobody comes to Yaya to say, 'Happy birthday', what more do you want?"

Seluk later clarified his comments in an interview with the BBC, after it was put to him that City had posted a message about Touré's birthday on their official Twitter feed.

"He got a cake but when it was Roberto Carlos's birthday, the president of Anzhi gave him a Bugatti," said Seluk. "I don't expect City to present Yaya with a Bugatti, we only asked that they shook his hand and said 'we congratulate you'. It is the minimum they must do when it is his birthday and the squad is all together."